I think Logitech makes the best keyboards. The lighting options are pretty awesome and can match any rig. I like being able to customize the key colors all over the keyboard. If you're not a wrist-rest user, this keyboard is pretty much your standard rectangle.
As far as the phone mount with the phone app ....If I can't have a screen close to monitor level, it's not something I'm going to look at while gaming anyway. This integration is what probably gives this keyboard a higher price tag and to me makes it not worth the $179 cost.
When I'm gaming, I'm looking at the monitor, not the keyboard. That up and down from what would be the phone mount location to the monitor is just silly. Logitech needs to come up with something better than screens on the keyboard. There's a reason other companies aren't doing this too. Anything that takes your vision away from the screen while gaming (especially with shooters), puts you at a disadvantage.
Logitech should release another version of this keyboard without the associated cost of the phone mount.